Block-based video coding algorithms may create visible blocking artifacts in the decoded images. These artifacts, caused by block-based motion compensation and residual transform coding, have extensively been studied for the encoding of single view sequences.
The deblocking filter is a proven tool to suppress visually unpleasant blocking artifacts. It has also been proved that deblocking filters can increase coding efficiency if used in the prediction loop, as in the International Organization for Standardization/International Electrotechnical Commission (ISO/IEC) Moving Picture Experts Group-4 (MPEG-4) Part 16 Advanced Video Coding (AVC) standard/International Telecommunication Union, Telecommunication Sector (ITU-T) H.264 recommendation (hereinafter the “MPEG-4 AVC standard”).
The deblocking filter smoothes over the reconstructed pixels near the block boundaries. An effective deblocking filter should adjust the filtering strength according to the nature of the signal and the values of certain coding parameters. However, a high level of adaptability of the filter will introduce an undesirable high complexity in implementation.
Several previously proposed multi-view video coding (MVC) architectures include cross-view prediction to achieve better coding efficiency compared to simulcast (compressing each view independently). However, there is no previous art on deblocking filter design in the framework of multi-view video coding.